From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933780Ab1IJSI4 (ORCPT ); Sat, 10 Sep 2011 14:08:56 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:46079 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933733Ab1IJSIz (ORCPT ); Sat, 10 Sep 2011 14:08:55 -0400 Date: Sat, 10 Sep 2011 14:08:49 -0400 From: Christoph Hellwig To: Konrad Rzeszutek Wilk Cc: linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com, JBeulich@novell.com, jeremy.fitzhardinge@citrix.com, axboe@kernel.dk Subject: Re: [PATCH 1/3] xen/blk[front|back]: Use the full FLUSH | FUA instead of just FLUSH. Message-ID: <20110910180849.GA6621@infradead.org> References: <1315593060-20031-1-git-send-email-konrad.wilk@oracle.com> <1315593060-20031-2-git-send-email-konrad.wilk@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1315593060-20031-2-git-send-email-konrad.wilk@oracle.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 09, 2011 at 02:30:59PM -0400, Konrad Rzeszutek Wilk wrote: > During a FLUSH we can pass sector number that we want to > have flushed - which is what FUA requests are. No, that is not the case. REQ_FLUSH without data -> pure flush REQ_FLUSH with data -> preflush plus write REQ_FUA -> write and ranged postflush